Identification of human parvovirus 4 genotypes 1 and 2 in Chinese source plasma pools

Parvovirus B19 and Parvovirus 4 infections among healthy blood donors; A prevalence report from Iran

Background

Parvoviruses, characterized by their tropism for blood cells, can manifest as asymptomatic infections. With their ability to persist in blood, assessing the prevalence of Parvovirus B19 (B19V) and Parvovirus 4 (PARV4) among healthy blood donors is essential for evaluating the potential transmission risks through blood transfusions, emphasizing the need for comprehensive screening protocols.

Methods

Four hundred blood donors participated in the study, with their blood specimens subjected to Real-Time PCR analysis for B19V and PARV4 nucleic acids after obtaining informed consent. Additionally, Complete Blood Count (CBC) assessments and determination of anti-B19 V-IgM and anti-B19 V-IgG antibody titers were performed using Enzyme-Linked Immunosorbent Assay (ELISA) for all collected samples.

Results

The results reveal that 12 out of 400 individuals (3 %) exhibited positive results for B19V DNA, while 6 out of 400 individuals (1.5 %) tested positive for PARV4 DNA. Additionally, 8 out of 400 individuals (2 %) displayed positive results for anti-B19V IgM, and 306 out of 400 individuals (76.5 %) exhibited positive results for anti-B19 IgG. Notably, one donation from a donor presenting anti-IgM antibodies was subsequently confirmed as B19V DNA-positive through Real-Time PCR. In the analysis of CBC, a significant disparity in platelet levels was observed between B19V-positive donors, PARV4-positive donors, and B19V-negative donors.

Conclusions

The study suggests that individuals at high risk, lacking detectable B19V antibodies, should undergo systematic screening and exclusion. This precaution is intended to minimize potential contamination risks within the studied cohort, despite the undefined pathogenesis and clinical implications of PARV4.

Study on genotyping and coinfection rate of human parvovirus 4 among the HTLV-I/II infected blood donors in Khorasan Razavi, Iran

Human Parvovirus 4 (PARV4) is an emerging virus infecting individuals with other blood-borne diseases. This study aimed to determine the prevalence of PARV4 in confirmed HTLVI/II positive samples from blood donors, assessing PARV4 viral load (DNA) and genotyping.

METHODS

A novel qReal-Time PCR, based on a plasmid construct, was developed to simultaneously detect all three PARV4 genotypes using in-house primers and probes. Positive qPCR samples were subjected to nested PCR amplification and subsequent sequencing. Phylogenetic trees were constructed using the Neighbor-joining (N.J.) method.

RESULTS

The coinfection rate of PARV4-DNA in HTLVI/II confirmed infected donors, who were previously deferred, was 14.4 % (13 out of 90), with no observed association with donation status (p = 1.0). Phylogenetic analysis indicated that PARV4-positive samples closely resembled genotype 2 in Iran.qPCR quantification demonstrated significant PARV4 viral loads in positive samples, ranging between 104 and 106 DNA copies/mL of serum.

CONCLUSION

This study presents the first evaluation of HTLVI/II and PARV4coinfection rates among blood donors. Notably, elevated PARV4-DNA titers were detected in HTLVI/II-positive donors. Given PARV's resistance to standard plasma refinery inactivation methods and the absence of its targeted inactivation, its potential impact remains a concern.

Identification of human parvovirus 4 genotypes 1 and 2 in Chinese source plasma pools

Human parvovirus B19 (B19V) and human parvovirus 4 (PARV4) are known to infect humans and transmit through contaminated blood and blood products. Globally, three genotypes of B19V, as well as PARV4, have been identified, respectively. The existence of different B19V genotypes in Chinese plasma donors has been investigated, however, the data regarding PARV4 were not available. The main objective of this study is to identify the genotypes of PARV4 circulating in Chinese plasma donors. By using a duplex quantitative polymerase chain reaction assay adapted for all genotypes of B19V and PARV4, 78 source plasma pools for fractionation were screened and quantified. Results showed that positive rates of B19V and PARV4 DNA in plasma pool samples were 25.64% and 14.10%, respectively. PARV4 sequences in two positive samples were next genotyped, and these two sequences belonged to PARV4 genotypes 1 and 2, respectively. In conclusion, the data present demonstrate the existence of PARV4 genotypes 1 and 2 in Chinese plasma donors for the first time and also show the relatively lower prevalence and level of PARV4 DNA in Chinese plasma donors in comparison with that of B19V DNA.

At least two PARV4 genotypes, 1 and 2, were currently present in China.

The prevalence and level of PARV4 DNA in Chinese plasma donors were relatively lower in comparison with that of B19V DNA.

The rate of B19V and PARV4 coinfection in Chinese source plasma pools was low.

Efficacy and safety of decontamination for N95 respirator reuse: a systematic literature search and narrative synthesis

PURPOSE

Under times of supply chain stress, the availability of some medical equipment and supplies may become limited. The current pandemic involving severe acute respiratory syndrome coronavirus 2 has highlighted limitations to the ordinary provision of personal protective equipment (PPE). For perioperative healthcare workers, N95 masks provide a stark example of PPE in short supply necessitating the creation of scientifically valid protocols for their decontamination and reuse.

METHODS

We performed a systematic literature search of MEDLINE, Embase, Cochrane CENTRAL databases, and ClinicalTrials.gov to identify peer-reviewed articles related to N95 mask decontamination and subsequent testing for the integrity of mask filtration and facial seal. To expand this search, we additionally surveyed the official statements from key health agencies, organizations, and societies for relevant citations.

RESULTS

Our initial database search resulted in five articles that met inclusion criteria, with 26 articles added from the expanded search. Our search did not reveal any relevant randomized clinical trials or cohort studies. We found that moist mask heating (65-80°C at 50-85% relative humidity for 20-30 min) and vaporous hydrogen peroxide treatment were supported by the literature to provide consistent viral decontamination without compromising mask seal and filtration efficiency. Other investigated decontamination methods lacked comprehensive scientific evidence for all three of these key criteria.

CONCLUSIONS

N95 mask reprocessing using either moist heat or vaporous hydrogen peroxide is recommended to ensure healthcare worker safety.

Anesthesiologist behavior and anesthesia machine use in the operating room during the COVID-19 pandemic: awareness and changes to cope with the risk of infection transmission

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease [coronavirus disease 2019 (COVID-19) infection] first appeared in December 2019 in China and is now spreading worldwide. Because SARS-CoV-2 can be transmitted via aerosols and surface contaminations of the environment, appropriate use of anesthesia machines and appropriate behavior in the operation room (OR) are required specifically in relation to this disease. The use of high-performance hydrophobic filters with a high rate of virus rejection is recommended as the type of viral filter, and surgical team behaviors that result in aerosol splashes should be avoided. Appropriate hand hygiene by the anesthesiologist is crucial to prevent unexpected environmental contamination. When the anesthesia machine is used instead of an intensive care unit ventilator, it is important to keep the fresh gas flow at least equal to the minute ventilation to prevent excessive humidity in the circuit and to monitor condensation in the circuit and inspiratory carbon dioxide pressure. In addition, both the surgical smoke inherent in thermal tissue destruction and the surgical team's shoe soles may be factors for the presence of SARS-CoV-2 in the operating room. Ensuring social distancing-even with a mask in the OR-may be beneficial because healthcare providers may be asymptomatic carriers. After the acute crisis period of COVID-19, the number of cases of essential but nonurgent surgeries for waiting patients is likely to increase; therefore, optimization of OR scheduling will be an important topic. Anesthesiologists will benefit from new standard practices focusing on the prevention of COVID-19 infection.

Air contamination with SARS-CoV-2 in the operating room

Angiotensin converting enzyme 2 (ACE2) is a target cell receptor for internalization and proliferation of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). When ACE2-highly expressed tissues are manipulated, SARS-CoV-2 containing aerosols may be generated. Normal breathing and speaking are capable of producing aerosols so mask ventilation, suction of airway tract and bucking during tracheal intubation and extubation are clinical procedures capable of significant aerosol production. Whilst no data have been reported on the distribution of SARS-CoV-2 in the operating room (OR), contamination in the OR can be estimated from the intensive care unit (ICU) data. ICU data showed that SARS-CoV-2 was detected on all types of surface and in air within about 4 m from coronavirus disease 2019 (COVID-19) patients. High concentrations of SARS-CoV-2 was detected in the personal protective equipment (PPE) removal room and medical staff office. Submicron virus-laden aerosols could result from resuspension of particles containing SARS-CoV-2 sticking the PPE surface; removal could produce the initial velocity. Supermicron virus-laden aerosol could come from floor deposited SARS-CoV-2, which were carried across different areas by medical staff (e.g., shoe). Knowledge of aerosol generation and distribution in the OR will aid the design of strategies to reduce transmission risk.